There is serious concern throughout the world that with the increasing deployment of reprocessing facilities that there is an increased likelihood of the further proliferation of nuclear weapons. This concern is due to the fact that essentially all reprocessing methods used heretofore are derived from the processes originally developed during or shortly after World War II for producing plutonium for nuclear weapons. These processes are undesirable because they have the potential to make purified fissionable materials available and therefore susceptible to diversion by terrorist groups. In addition, there is international concern because such reprocessing plants could readily be converted over to the extraction of weapons material by a change of intention by a government which had previously pledged by treaty to forego the production of nuclear weapons.
In answer to this threat Milton Levenson and Edwin Zebroski conceived of a process for reprocessing spent nuclear reactor fuel which makes plutonium highly resistant to diversion. Their concept, which is called The CIVEX Process, includes a combination of changes in the method of reprocessing spent fuel and changes in the design of a reprocessing plant. The CIVEX concept is disclosed in the U.S. patent application entitled "METHOD AND APPARATUS FOR PROCESSING SPENT NUCLEAR REACTOR FUEL" Ser. No. 878,392 which was filed on Feb. 16, 1978.
Within a fuel reprocessing facility a sampling station is a major focus for diversion because it is a point where plutonium containing liquid can be obtained directly without arising suspicion. It is also a point where radiation exposure is minimized and where equipment is readily accessable for transporting radioactive materials. A sampling station is a shielded outlet where radioactive samples are taken by plant personnel in order to monitor the status of the process. These samples are taken at sampling stations located throughout the plant. In a typical plant there are between 40 and 50 such sampling stations. Samples are taken at various rates depending on what is being sampled and which step is occurring in the process. Samples are normally taken either hourly, once per shift, or daily.
In the past sampling stations have been designed principally with the objectives of shielding plant personnel from radiation exposure and insuring that representative samples of the process was taken. It is believed that aside from these objectives no attempt has heretofore been made to limit the amount and frequency of the samples taken. It is also believed that no attempt has heretofore been made to control physical access to sampling stations so that the diversion of plutonium containing liquid could be prevented.
The present invention is directed to overcoming one or more of the problems as set forth above.